US 2008/0024470 discloses an invisible, light-transmissive display system in a light resistant material. Substantially invisible, tapered, light-transmissive holes are penetrated in a light-transmissive pattern through at least a portion of the light resistant material, using a laser beam having a focal width less than the smallest diameter of the tapered holes. The main objective consists in an application as LED indicators, e.g. for batteries or standby light signals which are intended to be integrated invisibly into a material, wherein the holes are intended to be very small per se, the distance between the holes is adapted to the resolving power of the viewer.